Fuel-feeding system



Feb. 3, 1.931. C, HOFBAUER 1,791,130

FUEL FEEDING SYSTEM Filed Aug. l5. 1925 T cl.

T0 INLET MANIFOLD INVENTOR BY {WMM ATTORNEY Patented Feb. 3,1931

-GASIEAR HGFBAUER, OF NEW YORK, N. Y.,

PATENT ourlet ASSIGNOR 'TO PBAIlOUNT CARBURETOR CORPORATION, 0F vNEVI YGRK, N. Y., A CORPORATION 0F NE-W YORK FUEL-FEEDING SYSTEM Application filed August 15, 1925.

My invention relates generally to fuel feeding systems intended especially for explosive engines, and more particularly to anv apparatus in which the variations in pressure incident to the operation of the engine is caused to produce a fuel feed from a main feed tank at' any level to the level at which the fuel is to be employed or used and coordinately involves an apparatus whereby a liquid fuel is reduced to a gaseous state and combined with air in explosive proportions or to mixtures suitable for internal combustion engines.

The invention includes the method whereby a mixture is made suitable rfor consumption in a hydro-carbon engine of the internal combustion variety, independent of the relationship or position which the main source of fuel supply may have to the point of consumption, and further provides apparatus having means of controlling the air to fuel ratio, tending to give maximum efficiency of combustion with the minimum amount of refinement of adjustment and variation due to construction and operation.

For purposes of convenience, I have illustrated and will describe my apparatus as associated with an automobile of the internal combustion engine type, although as will be understood as this specification is read, all phases or features of the invention are not so necessarily limited since certain features or phases have or may have a Wider field of utility and for this reason, unless specifically so limited in the claims, my invention will be understood as having a much broader field of utility. a

One of the objects of my invention is the provision of an arrangement whereby a liquid fuel which may be ata lower level is presented in the form of a vaporized mixture without the requirement of any adjustable parts or of parts requiring a Arefinement of dimensions or any extreme accuracy of assembly and to an arrangement to which the Y parts when assembled require no further adjustment.

Another object of my invention is the provision with a source of fuel supply at a lower level of a method and apparatus whereby a mixture is produced at the lower level and Serial No. 50,354.

adjacent the source of supply so that the proby lem of'feeding the mixture to the point of use is one which involves to a considerable extent the laws of the movement and mixture of gases.

Where the liquid fuel is vaporized or reduced to a gaseous state immediately adjacent the source of supply andfis fed toa point of combustion at a higher level which is at afdistance from the source of supply, as where the lsource of supply is a tank in the rear of an automobile, the problem of providing a stable explosive mixture is somewhat dierent from that generally present where the mixture is produced immediately adjacent the point of use. By means of my invention I attain a stable mixture by initially producing a vaporized mixture immediately adjacent the rear tank and feeding such mixture to the point of consumption, adjacent which the mixture may be automatically diluted or enriched as required by running conditions. i

From thel standpoint of the character of mixture produced as well as from the stand'- f point of initial cost and adjustment, I have found the jet method of fuel mixture production unsatisfactory for a number of reasons among which is the fact that such apparatus relies for its effectiveness upon the entrainment of a central column of gasoline dragged along by a surrounding column of air and another object of my invention is the provision of an arrangement whereby the mixing of the air andthe fuel is produced by a column of flowing air drawn at high velocity through a column of fluid fuel. In this way not only is the surface exposure of the fuel increased but the vaporizing action of the column of air made more effective and is constant as the moving inertia of the column of liquid fuel is eliminated as'a factor in the production of the mixture.

Infcarrying out my invention, I provide a direct connection between the tank interior and the place at which there is a variation of pressure coincident with the operation of a hydrocarbon engine, so that the variations 1n pressure are at once transmittedy to a point of discharge inthe rear tank so that with the production of a decrease in pressure at such point, there will be produced simultaneously a diminished pressure at a point in the conduit adjacent the rear tank, so that the atmospheric pressure will cause the liquid fuel to be forced out the rear tank.

l also connect a peint in a conduit .subject to variations of pressure such as the manifold, with the atmosphere in such a way as to produce a flow of air at high velocity, and direct such flow of air to a point in the conduit along the line in which the flow of fuel is directed and inthe path of such fuel flow inducted as stated and preferably at a point adjacent the rear tank. rlhe apparatus is so constructed that this flow of air will cause or increase the vaporization of the fuel thus lifted out of the main source of fuel supply and produce an intimate mixture of the two, thus lightening the fuel. The mixture is then fed from its place of initial formation adjacent the rear tank at a speed at which the flow of air is progressing, and which is dependent upon the effective degree of vacuum below the throttle opening, and in such feeding movement it may be brought adjacent a heated surface such as the exhaust pipe so as not only to heat the mixture and produce a more ready admixture of the particles, but to still furth-er increase the velocity of its flow. rlhis mixture, preferably although not necessarily heated as already stated, is so fed into the inlet manifold as to cause it to have a rotating motion for the purposes of producing a still more intimate mixture and at this point, l provide for the automatic introduction of a still further quantum of air automatically controlled by thereffective degree of dierential pressure through the throttle opening. This quantum of air is also introduced so as to be presented in the form of an internal column iutroduced at a high velocity into the mixture initially formed and fed along as set forth.

The pressure below the throttle opening is maintained at a constant diferential pressure or vacuum as compared to the inlet manifold by au air controlled valve which is responsive to the variations in speed of the engine. 'l his is the only variable factor during operation and by means thereof it thus presents a constant low pressure head to the main source of fuel supply. is the air is the largest component of the mixture, the control of the mixture by having the air control as the only variable is of considerable importance, because any variation loy reason of operation or structural differences in design of the air valve, will cause a minimum variation in the operative efliciency of the combustion mixture which is supplied for consumption.

The apparatus is so constructed and arranged that the degree of vacuum at the inlet manifold below the throttle opening is progressively increased toward the source of fuel supply, so that at a point adjacent thereto, which in the preferred embodiment is the rear tank, a degree of vacuum of many times that present in the inlet manifold is produced.

For the attainment of these objects and such other objects as may hereinafter appear or be pointed out, l have illustrated one embodiment of my invention in the drawings, wherein:

Fig. l is a plan view of an automobile showing diagrammatically my apparatus associated therewith; and

Fig. 2 is a vertical section partly broken away lengthwise tiereof through a preferred form of my apparatus.

Upon viewing Fig. l of the drawing, it

will be observed that l show a conventional:

type of an automobile with a low level rear tank l0 from which fuel is fed by a pipe l1 into the engine l2 in which fuel is exploded or ignited and from which the exhaust products are discharged through the exhaust pipe 13 into the mufller lll.

Upon viewing F ig. 2 of the drawing, it will be observed that the fuel pipe ll is at all times open at its left in the direction of flow to the inlet manifold and at its right is open at all times to the conduit l5 leading into the rear tank l0 and preferably extends to a point adjacent the bottom thereoi0 at which point it is open to the rear tank, and a strainer 16 being provided at this point so as to prevent the entrance of any solid matter into the conduit 15.

ln this manner, the gasoline in the conduit l5 is subect to the variations in pressure to which the inlet manifold is subjected to, and with the production of a partial vacuum in the manifold a corresponding vacuum will be created in the conduit l5 and due to the fact that the rear tank l0 is always open to atmospheric pressure, the fuel in the conduit l5 will be forced upvardly.

l will now describe my method and apparatus for the vaporisatiou of fluid so raised and for its mixture with air so as to produce an explosive mixture. The conduit l5 is connected to the fuel pipe ll means of con-- nection EZ() which, as shown, comprises generally the head 2l, 1 irdly extending leg 22 and the downiw y extending leg 23. The portions 25 of the passage through the leg 22 is illustrated as of the same crosssectional area and contour the fuel pipe 1l near the terminal tapering preferably from a point 26 to the neck 27 so as to provide a jjiassaffeway :28 which gradually widens and incr( es into the aforementioned desoribeil condiit portion Opening into the tapering passageway 28 at the neck Z7, is the enlarged chamber Q9 formed in the head 2O which narrows rapidly as shown 30 and merges into the neck 27.` The head 21 is preferably open to the atmosphere at its rear' or rigl'it end in Fig. 2 for' its full cross-sectional area and-,threaded inv said open end, is the'funnel shaped member 32 tapering fr rn a width corresponding to the widest portion of the head 21 to the narrow opening 33 and having a curvature conducive to best results which is shown as opening into the chamber 29 slightly in advance of the point where this chamber merges into the constriction or neck portion 27. This cha-mber is preferably of a size vso as to materially increase in cross-sectional area at the point where the inlet conduit leads thereinto.

which is fixed to the upper surface of the tank in any preferred or desired manner as by means of the eno'agement of the washer 38 with the bushing 39 depending from said fitting 37.

It will thus be seen that the inlet manifold is connected directly to the atmosphere through the conduits 11, 25, 28 and 29 and the funnel 32 so that any vacuum or reduced pressure in the inlet manifold will cause air to rush through the funnel 32 and into the passageway 28 and the velocity of this column of' air will depend upon the degree of vacuum produced in the inlet manifold below the throttle opening. The parte are preferably so positioned and arranged that the path of flowY will be for its major portion along a continuous straight line.

As has already been described, the drop in the pressure in the inlet manifold will also cause liquid fuel to be raised in the pipe 15 and into the chamber 29 where it will be partially or wiolly vaporized in this chamber and in its vaporized state the fuel will be dra-wn in the direction of andv through the passageway 28 and at this point, will be presented in the path of the column of air being aspirated in through the opening `33 of the funnel 32 and' due to the arrangement of the parts already described, such fuel will not only be further vaporized, but will also be caused to mix with the air introduced so as tov `oroduce a vaporized mixture immediately adjacent thereto.

The actionof causing the column of air aspirated in through the funnel 32 to impinge upon the vaporized fuel passing through the neck 27 will .not only tend to increase the velocity of the mixture but will also tend to cause the mixture to have a `whirling motion and as this mixture passes the neck 27 into the gradually widening passage 28, the character of the mixture will be still further improved and the degree of Yvaporization of the fuel increased. f The fact that the fuel mixture is fed from a point ad'- jaeent the rear tankk to a `point adjacent the inlet manifold will have an extremely benelicial effect in forming and maintaining a stable mixture of a satisfactory character and this end will be effected, by reason of vfeeding the fuel into the chamber 29 at an vacuums, l connect the left end of the conduit 11 to the inlet manifold in the manner` rshown onv the left in Fig. 2 of the drawing and upon viewing this part of. Fig. 2, it will be observed that the passage through the conduit l1 opens into the passage through theV connection 4lwhich has its reduced end threaded into the chamber 43 formedv in the part 44 projecting outwardly from the manifold fitting 45.

The hollow fitting 45 which is arranged at its upper end to be connected with the inlet manifold by means of the collar or flange 7 7 of conventional design having screw connecting means 7 8 formed therein. The throat 79 of thefltting is preferably of uniform diameter and has mounted therein a throttle valve 80 preferably of the butterfly variety. Below the throat 79, the fitting vhas axed to its interior the collar 46 in any preferred or desired manner as by the set screw 47. This collar has the passageway 48 therethrough which widens outwardly towards its ends as shown at 49 and 50. Secured to the interior surface of the passageway in said ttingg; 45 in any preferred or desired manner as by threading is the coneshaped or funnel shaped collar or annulus 5l having its narrowed or discharge end 52 extending within and spaced from the lower outwardly widening mouth 50 of the collar 46 the two collars 46 and 5l being spaced apart to provide the annular chamber 53 therebetween leading into the annular inclined passageway 54 connecting the chamber 53 with the intake manifold through the passage 48, in the collar 46. The chamber 53, which as stated, is annular in shape, is open at 55 to the passage through the connection 4l.

From the description thus far given, it will be understood that the gaseous mixture formed in the fitting 20 and adiacent the `main tank is led into the fitting 45 and into the annular chamber 53 from which it discharges into the annular inclined passageway 54 from which in turn, it is led into the passage 48 which widens at its upper end as vshown at 49 and discharges through the throat 79 past the throttle 8O and opening Cdl formed by the same into the intake manifold. This manner of treatment of the gaseous mixture tends to produce complete vaporization of the fuel and a still better mixture, because, will be understood, as the mixture moves from the chamber 43 into the annular chamber 53 and then upwardly through the passage 54 into the passage 48, the mixture may be caused to have a whirling motion.

The fitting widens below the collars 5l to form the enlarged chamber 6l provided with the seat 62 upon which is received the gravity or other type valve 53 of any desired or preferred shape to control the admission into the chamber 61 of an additional supply of air from the passageway 63, which air is obtained in any preferred or desired manner from the atmosphere, it being preferably preheated by having the passageway 63 pass around the exhaust pipe.

As the vacuum in the manifold increases, for instance, at high speeds, the parts are so adjusted that at predetermined points in said increase, the valve 53 will be responsive to the increased vacuum and be lifted further from its seat and an increased supply of air will be admitted into the passageway d3 through the collars i6 and 5l and this air will talle the form of a column directed against and into the whirling mixture introduced through the passage 54.1., thus not only providing an additional supply of air, but providing this in a form in which it will tend to accelerate the flow of the gaseous mixture already formed and entering said passage /lS through the chamber 53 and the passage 54 and which mixture as already explained, is discharged.

It will be observed that the variation in the position of the throttle will tend to vary the degree of vacuum therebelow. This will however be maintained constant for each throttle opening by the air valve 53 which is responsive thereto. rlhus, the main fuel supply will be under a constant head of pressure established just below the throttle in the throat 79, insuring a constant flow or supply of fuel mixture through the passage 35. The variations necessary to produce the variatiens in speed of the engine will be taken care of by the rate of flow of the mixture to the point of consumption. Thus, there will always be maintained a constant ratio of air to fuel, and any losses efficiency will be a lact-or of the operation of the air valve 53. ln this instance, the air the largest factor, inaccuracies in construction or operation of the parts controlling the air supply will have a minimized effect upon the combustion efficiency of the mixture of air and fuel. ln addition, adjustments may be made to affect the fuel supply within micr-ometric precision.

The fitting 20 forms what is in fact a mixing nozzle into which the fuel is introduced in the form of a column circumferentially disposed about the air inlet and the parts being so dimensioned and proportioned as to give higher vaporizing quality and lower lifting qualities at the immediate point of admixture as compared with the ordinary gas nozzle. ln certain respects at certain stages the effect produced is to project a stream of air through a sheet of fuel. The fuel is preferably introduced into said vaporizing nozzle at an angle to the direction along v-Jhich the air is introduced resulting in producing a whirling motion within said nozzle.

ln order to prevent back firing through the line li, l may provide in the chamber i3 any preferred or desired valve construction 70.

For purposes of priming the engine as when the engine starts cold, l have provided the arrangement shown bel-ow the valve 53 in Fig. 2 of the drawing for maintaining said valve upon its seat. rlhe arrangement comprises a bell crank lever 7l having a lost motion connection at the free end '.72 of one of its legs to the guiding stem 7 3 projecting downwardly from the valve 53', the manually operated pull rod Tl being connected to the free end of the other leg at 75 by means of the spiral spring 76. Thus the full suction of the inlet point will be exerted upon the fuel outlet when desired.

lt will be observed that my apparatus generally is suitable for preparing the fuel for consumption in an internal combustion engine whi ch makes use of a hydro-Carbon fuel, preferably in liquid forni. However, though m apparatus is designed for use with the liquid fuel of the hydro-carbon variety, l consider it within the scope of my invention to use my apparatus with fuels in the gaseous or vapor phase or liquid phase including solids in finely divided form or the combined phases. Also though l have described my invention for use in connection with a main source of fuel supply arranged at the rear of an automobile, it may be positioned at any place intermediate the main source of supply and the point of consumption, or with a main source of supply located at any convenient position in reference to the point of consumption. Further, though l have described my invention preferably used in conjunction with the. inlet manifold, it will be observed that l contemplate as included within the scope of my invention, the use thereof in connection with the inlet ports, of a single cylinder or groups of cylinders of multiple cylinder engines whether connected jointly to a single manifold or not, and though l have illustrated my apparatus in connection with the inlet manifold, l mean to include within the scope of my invention, the use thereof at any point producing a variation .in pressure as compared with the atmosphere as at a point below the oint con-- nection of the inlet ports, making up the manifold and controlled by a single throttle let, said latter inlet being circumferentially disposed to said former inlet.

In witness whereof, I have hereunto signed opening.

Having thus described my invention and illustrated its use, what I claim as new and desire to secure by Letters Patent, is:

l. In a fuel feeding system for an` internal combustion engine operable by the engine induction, a low level fuel tank, and a mixing nozzle adjacent said tank operated by the engine induction, said mixing nozzle including an air inlet and a fuel inlet, said latter inlet being angularly disposed to said former inlet and adapted to give a whirling movement at the point of intersection of the two inlets.

2. In a fuel feeding system, for an internal combustion engine operable by the engine induction, a low level fuel tank, and a mixing nozzle adjacentsaid tank operated by the engine induction, said mixing nozzle including an air inlet and a fuel inlet, said latter inlet being circumferentially disposed to said former inlet and adapted to give a whirling movement at thepoint of intersection of the two inlets.

8. In a fuel feeding system, for an internal combustion engine operable by the engine induction, alow level fuel tank, and a mixing' nozzle adjacent said tank operated by the engine induction, said mixing nozzle including an air inlet and a fuel inlet, said latter inlet being angularly disposed to said former inletand adapted) to give a whirling movement at the point of intersection of the two inlets, and a secondary mixing nozzle adjacent said engine intake.

1l. In a fuel feeding system, for an internal combustion engine, operable by the engine induction, a low level fuel tank, and a mixing nozzle adjacent said tank operated by the engine induction, said mixing nozzle including an air inlet and a fuel inlet, said latter inlet being angularly, circumferentially disposed to said former inlet so as to give a whirling movement at the point of intersection of the two inlets, and a secondary mixing nozzle adjacent said engine intake, said secondary nozzle including an air inlet and a fuel inlet, said former inlet being angularly disposed to said former inlet so as to give-a whirling movement at the point of intersection of the two inlets. f

5. In a fuel feeding system, for an internal combustion engine operable by the engine induction, a low level fuel tank, and a mixing nozzle adjacent said tank, operated by the engine induction, said mixing nozzle including an air inlet and a fuel inlet, said latter inlet being so disposed and arranged to said former inlet so as to give a whirling movement at the point of intersection of the two inlets, and a secondary mixing nozzle adjacent said engine intake, said secondary nozzle including an air inlet and a fuel inmy name. 

